1. Field of the Invention
The present invention relates to a cleaning device, and more particularly to a cleaning device for use in cleaning the surface of moving members in image forming apparatus. In addition, the present invention also relates to a method for preparing the cleaning device. Further, the present invention relates to an image forming apparatus and a process cartridge using the cleaning device.
2. Discussion of the Background
Image forming apparatus for use as copiers and printers typically produce images by the following method:    (1) an electrostatic latent image is formed on an image bearing member (hereinafter sometimes referred to as a photoreceptor);    (2) the electrostatic latent image is developed with a developer including a toner to visualize the latent image as a toner image;    (3) the toner image formed on the photoreceptor is transferred to a receiving material optionally via an intermediate transfer medium; and    (4) the toner image is fixed on the receiving material, resulting in formation of a fixed image on the receiving material.
In such image forming apparatus, a small amount of toner particles remain on the surfaces of the photoreceptor and the intermediate transfer medium even after the toner image is transferred to a receiving material. Therefore, the image forming apparatus include one or more cleaning devices for cleaning the surface of the photoreceptor and the intermediate transfer medium. For this purpose, blade cleaning devices which remove residual toner particles while rubbing off the toner particles with a sheet (hereinafter referred to as a blade) are preferably used. Alternatively, brush cleaning devices which remove residual toner particles while scraping off the toner particles with a brush roller which is arranged so as to be rotated in pressing-contact with the photoreceptor. Recently, combination cleaning devices in which both a brush cleaning device and a blade cleaning device are arranged such that the brush cleaning device is located on an upstream side from the blade cleaning device relatively to the rotation direction of the photoreceptor are widely used.
Published unexamined Japanese patent application No. (hereinafter referred to as JP-A) 2001-188452 discloses a cleaning device in which both a brush cleaning device, which pulverizes residual toner particles to form fine toner particles, and a blade cleaning device, which scrapes off the fine toner particles, are arranged such that the brush cleaning device is located on an upstream side from the blade cleaning device relatively to the rotation direction of the photoreceptor.
JP-A 2003-043885 discloses a solid lubricant applying device which includes a brush roller and a lubricant, wherein the brush roller is contacted with both the lubricant and the photoreceptor while moving in a direction. The brush roller applies the lubricant to the surface of the photoreceptor to improve the cleanability of the photoreceptor. In this lubricant applying device, a contact member is also provided on a downstream side from the lubricant relative to the rotation direction of the brush roller such that the angle formed by a line C-A and a line C-B is greater than 180° wherein the point C is the center of the brush roller, the point A is an end point of the contact member which finally touches the brush roller and the point B is a contact point of the photoreceptor which firstly contacts the brush roller.
In addition, JP-A 2001-235987 discloses a cleaning device which includes a cleaning brush configured to rub the surface of a photoreceptor, a cleaning blade configured to scrape off residual toner particles from the surface of the photoreceptor, a flicker member configured to remove residual toner particles from the cleaning brush and a lubricant which is provided on the flicker member and which is coated on the surface of the photoreceptor by the cleaning brush; and an image forming apparatus using the cleaning device.
However, since a new cleaning brush has a strong cleaning ability, the amount of toner particles remaining on the surface of the photoreceptor is small after the surface of the photoreceptor is cleaned by such a new cleaning brush. Too small an amount of toner particles do not serve as a lubricant, and thereby the adhesion of the cleaning blade to the photoreceptor is increased, resulting occurrence of a problem (hereinafter a blade-rolling problem) in that the tip of the cleaning blade is turned by the surface of the photoreceptor so as to be bent inwardly along the surface of the photoreceptor. After repeated use, the cleaning brush contains residual toner particles in its hairs, and thereby a proper amount of toner particles are fed to the cleaning blade, resulting prevention of the blade-rolling problem mentioned above.
Because of these reasons, a need exists for cleaning device which can well clean the surface of an image bearing member without causing the blade-rolling problem whether the cleaning device is brand-new or not (i.e., or is repeatedly used).